Postexertional Cardiac Asystole in a Young Man Without Organic Heart Disease

Excerpt

Hypotension and syncope are common in erect subjects after exhaustive exercise of short duration (1, 2). Persistent postexercise peripheral arterial vasodilitation coupled with impaired venous return have been implicated as mediating events (3). Sinus pause with ventricular asystole is an unusual cause of postexercise syncope and has been ascribed to an excessive vagal response (4-7). We report a case of reproducible postexertional sinus pause with ventricular asystole and syncope and assess the effects of vagolytic and beta-adrenergic blocking agents.

A previously healthy 22-year-old man had a syncopal episode several seconds after maximal exertion pedaling a bicycle up-hill. Results of physical